If you invest in mining stocks across more than one country, you will encounter three different sets of initials attached to resource estimates and technical reports: NI 43-101 in Canada, JORC in Australia, and S-K 1300 in the United States. Each is a mandatory disclosure standard for mining companies listed on the major exchanges in their respective jurisdictions.
On the surface they may look like three different systems. In practice, they share a common foundation and are more similar than they are different. This guide explains exactly where they align, where they differ, and what that means for investors comparing mining companies across borders.
The Common Foundation — CRIRSCO
All three standards draw from the same source: the Committee for Mineral Reserves International Reporting Standards, known as CRIRSCO. CRIRSCO was formed in 1994 to create a globally consistent framework for mining disclosure, bringing together the major national standard-setting bodies from Canada, Australia, the US, South Africa, and other major mining jurisdictions.
The result is that NI 43-101, JORC, and S-K 1300 all use the same fundamental architecture:
- The same resource and reserve classification system — Inferred, Indicated, and Measured resources, and Probable and Proven reserves
- The same underlying principle — all technical disclosures must be prepared or signed off by an independent, credentialed expert
- The same core goal — protecting investors from misleading or unverified mining claims
This common foundation is what allows the three standards to be treated as broadly equivalent by the London Stock Exchange, the Hong Kong Stock Exchange, and other international markets that accept mining disclosure reports prepared under any of the three frameworks.
How They Are the Same
At the level that matters most to retail investors, NI 43-101, JORC, and S-K 1300 are functionally the same in the following ways:
- Resource and reserve definitions — the terms Inferred, Indicated, Measured, Probable, and Proven mean exactly the same thing across all three standards. A Measured resource under NI 43-101 is equivalent to a Measured resource under JORC and a Measured resource under S-K 1300.
- Independent expert requirement — all three require an independently credentialed expert to prepare or sign off on technical disclosures. Under NI 43-101 and S-K 1300 this person is called a Qualified Person (QP); under JORC they are called a Competent Person (CP). The qualification criteria — university degree, professional membership, minimum five years of relevant experience — are substantively the same.
- Prohibition on mixing categories — all three standards prohibit adding Inferred resources to Indicated or Measured resources, and prohibit using Inferred resources as the basis for economic analysis.
- Transparency requirements — all three require disclosure of the material assumptions, methodologies, and data behind any estimate. Companies cannot simply publish a number without context.
How They Differ
Despite sharing the same foundation, the three standards do have meaningful differences that become relevant for certain types of investors and transactions:
- Jurisdiction — NI 43-101 applies to TSX and TSXV-listed companies; JORC applies to ASX-listed companies; S-K 1300 applies to NYSE, NASDAQ, and other SEC-reporting companies. A company must follow the standard of the exchange it is listed on.
- The expert’s name — Qualified Person (QP) under NI 43-101 and S-K 1300; Competent Person (CP) under JORC. In practice the roles and requirements are nearly identical.
- Report format and content requirements — while the core content is similar, there are differences in how reports must be structured, what specific sections are required, and how certain types of data must be presented. A NI 43-101 technical report and a JORC-compliant report prepared for the same project may look somewhat different even if they report the same underlying numbers.
- Regulatory history and maturity — NI 43-101 (2001) and JORC (first edition 1970s, current 2012 edition) are more established than S-K 1300 (2021), though all three are now mature frameworks with track records of regulatory enforcement.
- Canadian MJDS exemption — Canadian companies dual-listed in the US using Form 40-F are exempt from S-K 1300 and continue to file under NI 43-101. This is why many TSX-NYSE dual-listed miners use NI 43-101 reports for both their Canadian and US regulatory obligations.
Are They Interchangeable?
For most practical purposes, yes — but with caveats. NI 43-101 and JORC reports are widely accepted as interchangeable for dual-listed companies, and both are accepted by the London Stock Exchange and Hong Kong Stock Exchange. The SEC now accepts JORC and NI 43-101 prepared reports from foreign private issuers under certain conditions.
However, each standard has jurisdiction-specific nuances, and a company that simply relabels a report prepared under one standard as compliant with another without a proper review by a qualified professional is taking regulatory risk. For any formal transaction — a financing, an acquisition, a stock exchange listing — independent verification that a report meets the specific requirements of the applicable standard is essential.
A Quick Reference Comparison
- Full name: NI 43-101 = National Instrument 43-101 Standards of Disclosure for Mineral Projects
- Full name: JORC = Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves
- Full name: S-K 1300 = Subpart 1300 of Regulation S-K
- Jurisdiction: NI 43-101 = Canada (TSX/TSXV) | JORC = Australia and New Zealand (ASX) | S-K 1300 = United States (NYSE/NASDAQ)
- Expert title: NI 43-101 = Qualified Person (QP) | JORC = Competent Person (CP) | S-K 1300 = Qualified Person (QP)
- Governing body: NI 43-101 = Canadian Securities Administrators / CIM | JORC = Joint Ore Reserves Committee | S-K 1300 = US Securities and Exchange Commission
- Established: NI 43-101 = 2001 | JORC = 1970s (current edition 2012) | S-K 1300 = 2021
- CRIRSCO member: All three — Yes
- Resource disclosure: All three — Yes (S-K 1300 added this in 2021)
What This Means for Investors
When comparing resource estimates from a Canadian, Australian, and US-listed mining company, you can now use the same classification framework as a baseline. The numbers are not perfectly comparable in every case — deposit geology, commodity type, and study stage all matter — but the definitions mean the same thing across all three standards.
The most practical implication is this: if you are evaluating a copper project reported under NI 43-101 against a copper project reported under JORC, an Indicated resource is an Indicated resource in both cases. The confidence level and classification methodology are equivalent. The QP and CP requirements are equivalent. The prohibition on using Inferred resources in economic projections is equivalent.
Where differences in output arise between reports on similar projects, they are more likely to reflect genuine geological differences, different stages of study, or different commodity price assumptions — not the reporting standard itself.
Key Takeaways for Investors
- All three standards share the same CRIRSCO foundation and use the same resource and reserve classification definitions
- The expert requirement — QP under NI 43-101 and S-K 1300, CP under JORC — is functionally equivalent across all three
- The standards are broadly interchangeable for comparative purposes and are accepted by major international exchanges
- Jurisdiction determines which standard applies — follow the listing exchange
- Canadian companies dual-listed in the US are typically exempt from S-K 1300 and file under NI 43-101 instead
- Compliance with any of the three standards does not guarantee a project is economically viable or a sound investment
SOURCES
1. CRIRSCO — Committee for Mineral Reserves International Reporting Standards: https://crirsco.com
2. Canadian Securities Administrators — NI 43-101: https://www.bcsc.bc.ca/securities-law/law-and-policy/instruments-and-policies/4-distribution-requirements/current/43-101
3. JORC Code 2012 Edition: https://www.jorc.org/docs/jorc_code2012.pdf
4. SEC — S-K 1300 Small Entity Compliance Guide: https://www.sec.gov/resources-small-businesses/small-business-compliance-guides/modernization-property-disclosures-mining-registrants-small-entity-compliance-guide
5. 911 Metallurgist — NI 43-101 and JORC comparison: https://www.911metallurgist.com/blog/national-instruments-ni-43-101-technical-reports/
6. Mining Doc — What are JORC and NI 43-101?: https://www.miningdoc.tech/question/what-are-jorc-ni-43-101-what-are-they-for/
DISCLAIMER
This article is an educational explainer based on publicly available regulatory documents and published industry sources. Information was current as of May 2026. Standards are subject to periodic revision — readers should consult the relevant regulatory body for the most current requirements.
Mining Markets Report has not received compensation from any company, regulatory body, or organization in connection with this article.
The information provided is for informational and educational purposes only and does not constitute financial, investment, legal, or professional advice. Readers should conduct their own due diligence and consult a qualified professional before making any investment decision.
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